Results 31 to 40 of about 329,423 (69)
Negativity‐preserving transforms of tuples of symmetric matrices
Proceedings of the London Mathematical Society, Volume 132, Issue 4, April 2026.Abstract Compared to the entrywise transforms which preserve positive semidefiniteness, those leaving invariant the inertia of symmetric matrices reveal a surprising rigidity. We first obtain the classification of negativity preservers by combining recent advances in matrix analysis with some novel arguments relying on well‐chosen test matrices, Sidon ...
Alexander Belton +3 more
wiley +1 more source
International Journal of Robust and Nonlinear Control, Volume 36, Issue 5, Page 2907-2926, 25 March 2026.ABSTRACT This study presents a novel Distributed Robust Adaptive Model Predictive Control (DRAMPC) for tracking in multi‐agent systems. The framework is designed to work with dynamically coupled subsystems and limited communication, which is restricted to local neighborhoods.
Fabio Faliero +2 more
wiley +1 more source
Schur-Convexity and Schur-Geometrically Concavity of Gini Mean
, 2007 The monotonicity and the Schur-convexity with parameters (s, t) in R² for fixed (x, y) and the Schur-convexity and the Schur-geometrically convexity with variables (x, y) in R²₊₊ for fixed (s, t) of Gini mean G(r, s; x, y) are discussed.
Shi, Huan-Nan
core +6 more sources
IET Circuits, Devices &Systems, Volume 2026, Issue 1, 2026.Typical resonant converter controllers are based on linearised averaged models, which have significant modelling errors when there are wide fluctuations in the input voltage, load and reference voltages. In this article, a piecewise affine (PWA) switching surface with active border tuning of affine sections, called the Partition Border Tuning (PBT ...
Mahdi Vakilfard +3 more
wiley +1 more source
Plank theorems and their applications: A survey
Bulletin of the London Mathematical Society, Volume 58, Issue 1, January 2026.Abstract Plank problems concern the covering of convex bodies by planks in Euclidean space and are related to famous open problems in convex geometry. In this survey, we introduce plank problems and present surprising applications of plank theorems in various areas of mathematics.
William Verreault
wiley +1 more source
Compactly‐Supported Nonstationary Kernels for Computing Exact Gaussian Processes on Big Data
Environmetrics, Volume 36, Issue 8, December 2025.ABSTRACT The Gaussian process (GP) is a widely used method for analyzing large‐scale data sets, including spatio‐temporal measurements of nonlinear processes that are now commonplace in the environmental sciences. Traditional implementations of GPs involve stationary kernels (also termed covariance functions) that limit their flexibility, and exact ...
Mark D. Risser +3 more
wiley +1 more source
Conformal optimization of eigenvalues on surfaces with symmetries
Journal of the London Mathematical Society, Volume 112, Issue 6, December 2025.Abstract Given a conformal action of a discrete group on a Riemann surface, we study the maximization of Laplace and Steklov eigenvalues within a conformal class, considering metrics invariant under the group action. We establish natural conditions for the existence and regularity of maximizers. Our method simplifies the previously known techniques for
Denis Vinokurov
wiley +1 more source
Super stable tensegrities and the Colin de Verdière number ν
Journal of Graph Theory, Volume 108, Issue 3, Page 401-431, March 2025.Abstract A super stable tensegrity introduced by Connelly in 1982 is a globally rigid discrete structure made from stiff bars and struts connected by cables with tension. We introduce the super stability number of a multigraph as the maximum dimension that a multigraph can be realized as a super stable tensegrity, and show that it equals the Colin de ...
Ryoshun Oba, Shin‐ichi Tanigawa
wiley +1 more source
An efficient flux‐variable approximation scheme for Darcy's flow
Numerical Methods for Partial Differential Equations, Volume 40, Issue 6, November 2024.Abstract We present an efficient numerical method to approximate the flux variable for the Darcy flow model. An important feature of our new method is that the approximate solution for the flux variable is obtained without approximating the pressure at all. To accomplish this, we introduce a user‐defined parameter delta, which is typically chosen to be
Rajan B. Adhikari +3 more
wiley +1 more source
Noise‐Tailored Constructions for Spin Wigner Function Kernels
Advanced Physics Research, Volume 3, Issue 6, June 2024.This work explores the parameterization of spin Wigner functions to efficiently represent the effects of probabilistic unitary noise on a quantum state. Block diagonalization of the noise operator algebra is used to reduce the required number of parameters while maintaining the Stratonovich–Weyl conditions for the representation.
Michael Hanks, Soovin Lee, M.S. Kim
wiley +1 more source